AWS Amplify branch environment variables

A branch's build and runtime read these. A write replaces the whole set, so a console edit made between our read and our write is lost.

Connection

What	This provider
Vendor	Amazon Web Services
Key	`aws-amplify-branch-env`
Availability	`available`. You can connect it today.
Credential we hold	`aws-role`
Values read back	yes
Activation	`on-next-deploy`

Direction	What it does
`import`	We read names and values out of the store into your environment.
`export`	We write names and values from your environment into the store.

on-next-deploy. A new value waits there and arrives with your next deploy.

Direction	Policies you can pick
`import`	`skip_existing`, `new_version`, `fail`
`export`	`create_only`, `overwrite`, `overwrite_and_prune`

How syncs work says what each one does.

You grant us access in your own AWS account. Pick one of these methods in the wizard.

We generate the shared value the grant is conditioned on, so you invent nothing.

Review the grant in code, then paste the role ARN back. Apply a rendered policy or template. You paste the result back into the wizard.

Set aside about 10 minutes.

It gives you:

Name	Label	Kind	What it is
`snippet`	Terraform	read only, a block to copy
`externalId`	External ID	read only, filled in for you	Already baked into the snippet. Only we can assume the role with it.

You paste back:

Field	Label	Kind	Required	What it is
`roleArn`	Role ARN	text	yes	The ARN the grant printed. We assume it once to check it before saving.

Create the role manually from the two policies below. Set up the grant by hand in the vendor's console. You paste the result back into the wizard.

Set aside about 10 minutes.

It gives you:

Name	Label	Kind	What it is
`penvAccountId`	Our AWS account ID	read only, filled in for you	The account the role trusts.
`roleName`	Suggested role name	read only, filled in for you	Unique to this attempt, so it cannot collide with a role another connection made.
`externalId`	External ID	read only, filled in for you	Required in the trust policy. Only we can assume the role with it.
`trustPolicy`	Trust policy	read only, a block to copy
`permissionsPolicy`	Permissions policy	read only, a block to copy

You paste back:

Field	Label	Kind	Required	What it is
`roleArn`	Role ARN	text	yes	The ARN the grant printed. We assume it once to check it before saving.

You set these when you connect. Every mapping on the connection shares them.

Field	Label	Kind	Required	Advanced	What it is
`region`	Region	text	yes	no	The region this connection reaches. One connection covers one region.
`accountId`	Account ID	text	no	yes	If supplied, the generated policy names the account instead of a wildcard.
`appId`	App ID	text	yes	no	The Amplify app this connection may touch. The grant is scoped to it.
`roleArn`	Role ARN	read only, filled in for you	yes	no	The role we assume. We fill it in from the grant you completed.

You answer these once per environment you map.

Field	Label	Kind	Required	Advanced	What it is
`branchName`	Branch	text	yes	no	The branch whose environment variables this maps onto.

We probe for these when we verify the connection.

Permission	Directions	Blocking	Without it
`sts:GetCallerIdentity`	every direction	yes	We cannot confirm which IAM identity this credential is.
`amplify:GetBranch`	every direction	yes	Preview cannot list the branch's variables.
`amplify:UpdateBranch`	`export`	yes	Export cannot write anything.